package Java.j2;

import java.util.Scanner;

public class AcWing_664 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        double a = sc.nextDouble();
        double b = sc.nextDouble();
        double c = sc.nextDouble();

        if(a+b>c && b+c>a && c+a>b){
            double perimetro = a+b+c;
            System.out.printf("Perimetro = %.1f",+perimetro);
        }else{
            double Area = (a+b)*c/2;
            System.out.printf("Area = %.1f",+Area);
        }
    }
}
